Smart Clip 2 is my choice

Smart-Clip2 Software v.1.12.03

We have implemented many important enhancements, which add more efficiency and productivity into your work with the new mobile phone models.

Added service support without rooting for:

MotoX / DROID ULTRA smartphones with Android 4.4.4

Motorola XT907, XT925, XT926 with Android 4.4.2

No need to unlock bootloader and perform root procedure in order to service your phone.
The solution allows you to perform Unlock / Repair IMEI operations on devices with non-unlockable bootloader (not supported by the phone manufacturer’s Bootloader Unlock program)

Improved repair procedure for Sony C1904 / C1905 / C2004 / C2005

Repaired IMEI will remain unchanged even after Master Reset operation from now on

Added new rooting method (#10), which works for many Android devices on 4.4.4 Kitkat

Some of the supported devices: Sony C6833, C6903; Huawei Y550 and more...

The list of models supported with "Autodetect" feature has been updated